Taxi　actual　operating　data　on　Beijing　urban　basic　freeway　section　is　taken　and　then　divided　according　to　driving　cycle　and　level　of　service　(LOS),　based　on　which　the　effect　and　potential　to　fuel　consumption　of　eco-driving　under　different　conditions　is　analyzed.　Analysis　of　variance　(ANOVA)　is　used　to　analyze　the　effect　to　fuel　consumption　of　driver　behavior　under　different　conditions.　The　result　shows　that　taxis　accelerating　and　decelerating　are　frequently　on　urban　basic　freeway　section.　With　the　improvement　of　LOS,　taxi　fuel　consumption　is　increased　under　the　condition　of　acceleration　and　steady　running,　but　it　is　reduced　under　deceleration.　The　main　vehicle　fuel　consumption　comes　from　the　accelerating　process　at　low　LOS.　Considering　the　conditions＇　contribution　to　total　fuel　consumption,　eco-driving　fuel-saving　potential　calculation　method　is　proposed　to　analyze　benefits　of　eco-driving.　It　turns　out　that　accelerating　process　has　highest　fuel-saving　potential　and　the　whole　fuel　consumption　reduction　on　urban　basic　freeway　section　could　be　11.18%　when　adopting　eco-driving.　Copyright　©　2015　by　Science　Press.